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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/arm/mach-picoxcell/common.c
Initial import
Diffstat (limited to 'arch/arm/mach-picoxcell/common.c')
-rw-r--r--arch/arm/mach-picoxcell/common.c86
1 files changed, 86 insertions, 0 deletions
diff --git a/arch/arm/mach-picoxcell/common.c b/arch/arm/mach-picoxcell/common.c
new file mode 100644
index 000000000..ec79fea82
--- /dev/null
+++ b/arch/arm/mach-picoxcell/common.c
@@ -0,0 +1,86 @@
+/*
+ * Copyright (c) 2011 Picochip Ltd., Jamie Iles
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * All enquiries to support@picochip.com
+ */
+#include <linux/delay.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/reboot.h>
+
+#include <asm/mach/arch.h>
+#include <asm/mach/map.h>
+
+#define PHYS_TO_IO(x) (((x) & 0x00ffffff) | 0xfe000000)
+#define PICOXCELL_PERIPH_BASE 0x80000000
+#define PICOXCELL_PERIPH_LENGTH SZ_4M
+
+#define WDT_CTRL_REG_EN_MASK (1 << 0)
+#define WDT_CTRL_REG_OFFS (0x00)
+#define WDT_TIMEOUT_REG_OFFS (0x04)
+static void __iomem *wdt_regs;
+
+/*
+ * The machine restart method can be called from an atomic context so we won't
+ * be able to ioremap the regs then.
+ */
+static void picoxcell_setup_restart(void)
+{
+ struct device_node *np = of_find_compatible_node(NULL, NULL,
+ "snps,dw-apb-wdg");
+ if (WARN(!np, "unable to setup watchdog restart"))
+ return;
+
+ wdt_regs = of_iomap(np, 0);
+ WARN(!wdt_regs, "failed to remap watchdog regs");
+}
+
+static struct map_desc io_map __initdata = {
+ .virtual = PHYS_TO_IO(PICOXCELL_PERIPH_BASE),
+ .pfn = __phys_to_pfn(PICOXCELL_PERIPH_BASE),
+ .length = PICOXCELL_PERIPH_LENGTH,
+ .type = MT_DEVICE,
+};
+
+static void __init picoxcell_map_io(void)
+{
+ iotable_init(&io_map, 1);
+}
+
+static void __init picoxcell_init_machine(void)
+{
+ of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
+ picoxcell_setup_restart();
+}
+
+static const char *picoxcell_dt_match[] = {
+ "picochip,pc3x2",
+ "picochip,pc3x3",
+ NULL
+};
+
+static void picoxcell_wdt_restart(enum reboot_mode mode, const char *cmd)
+{
+ /*
+ * Configure the watchdog to reset with the shortest possible timeout
+ * and give it chance to do the reset.
+ */
+ if (wdt_regs) {
+ writel_relaxed(WDT_CTRL_REG_EN_MASK, wdt_regs + WDT_CTRL_REG_OFFS);
+ writel_relaxed(0, wdt_regs + WDT_TIMEOUT_REG_OFFS);
+ /* No sleeping, possibly atomic. */
+ mdelay(500);
+ }
+}
+
+DT_MACHINE_START(PICOXCELL, "Picochip picoXcell")
+ .map_io = picoxcell_map_io,
+ .init_machine = picoxcell_init_machine,
+ .dt_compat = picoxcell_dt_match,
+ .restart = picoxcell_wdt_restart,
+MACHINE_END